Showcases of this type must therefore satisfy various kinds of requirements, in relation to the storage and integrity of the objects displayed. Moreover, of course, these showcases must ensure maximum visibility of the objects displayed.
In order to improve visibility, manufacturers of showcases try as hard as they can to use transparent materials—typically glass—for the walls of the showcase. As well as ensuring maximum visibility of the objects displayed, the extensive use of glass is often desired by designers of showcases because the transparency of the material allows the objects displayed to be given maximum visual impact.
Therefore, showcases have been developed having a base block with a case formed by panels on top; the base block houses all of the technical components necessary to ensure that the environment inside the case is protected and is thus normally closed by non-transparent walls, which hide all of the technical components from view; vice-versa, the walls of the case are made entirely or partially from glass, for the aforementioned reasons.
The possibility of access to the inside of the case, for the housing, removal or maintenance of the objects displayed, is normally obtained by providing for at least one of the side panels to be openable. For this purpose, opening supports of various kinds are used, which allow opening by rotation or roto-translation of the panel (more or less complex hinges) or by sliding (sliding guides). These opening supports must clearly ensure the correct closure of the openable panel, but must also allow an opening that is as wide as possible, so as to make access possible and easy also to arrange very large-sized objects (relative to the size of the showcase), possibly also in cases in which the weight of the object forces the uses of a fork lift or similar to move the object.
Therefore, there is a problem of maximising the degree of opening of the openable panel, even in the presence of panels made of transparent material.